1. Field of the Invention
The present invention relates to a method for efficiently producing a powder-coated support, which does not require a drying process and can use, without limitation, even a resin that hardly form a latex or an aqueous solution, and to a powder-coated support obtained by the production method, which exhibits less swelling and has excellent smoothness and glossiness.
2. Description of the Related Art
Conventional supports for use in image forming materials include, for example, base paper, synthetic paper, synthetic resin sheets, coated paper, and laminated paper. Among them, coated paper and laminated paper are particularly advantageously used for their high quality.
The coated paper and laminated paper are produced, for example, by a solvent coating process in which a thermoplastic resin is dissolved in an organic solvent and is applied to a base paper; an aqueous coating process in which a thermoplastic resin is formed into a latex or an aqueous solution (varnish) and is applied to a base paper; a dry laminate process in which a thermoplastic resin is dry-laminated onto a base paper; or a melt extrusion coating process.
However, the solvent coating process uses a deleterious organic solvent and thus adversely affects the environment.
In the aqueous coating process, the base paper swells upon coating due to water in the latex or the aqueous solution (varnish) and loses its smoothness. For example, Japanese Patent Application Laid-Open (JP-A) No. 04-234755 proposes a support for photographic printing paper. The support is prepared by forming a coated layer of composite particles containing polyolefin resin particles and a white pigment on a base sheet, heating, melting, and solidifying the coated layer to thereby form a resin coated layer on the base. However, according to the proposed technique, the particle dispersion is applied to the support (raw paper) and is dried, thus inviting swelling of the support. The resulting support has insufficient smoothness and glossiness. In addition, the aqueous coating process cannot be applied to resins that cannot yield latices or aqueous solutions.